Optimized decoupling concepts for digital VLSI circuits

A very common approach to reduce conducted and radiated emission caused by VLSI-circuits is using blocking capacitors at the noise-sources together with a sandwich consisting of a power- and a ground-plane. This paper shows the disadvantages of this approach and how to improve it by feeding the supply current through short pieces of microstrip or coplanar lines. In addition coils embedded in the PCB (printed circuit board) are used. These measures are improvements of the work presented by L.P. Janssen (1999). A strong reduction of RF-(radio-frequency)-disturbances along the supply system has been measured together with a reduced emission of radiation.